William a



(Nd Model.)

w. A. WEST.

TELEPHONE. No. 470,634. Patented M a r.8, 1892 line,

FIGJI.

ATTEST" INVENTOR h NITED STATES PATENT OFFICE.

WILLIAM A. WVEST, OF BELLEFONTAINE, OHIO, ASSIGNOR OF TWVO-TI-IIRDS TOW. H. WEST AND O. G. WEST, OE SAME PLACE.

TELEPHONE.

SPECIFICATION forming part of Letters Patent No. 470,634, dated March 8,1892. Application filed November 12, 1883- Serial No. 111,593. (Nomodel.)

To all whom, it may concern.-

Be it known that I, WILLIAM A. WEST, of Bellefontaine, Ohio, haveinvented certain new and useful Improvements in Telephones,

of which the following is a specification.

My invention consists of a reactionary reinforcing device which may beplaced at an intermediate point on a telephone-circuit and serve toimpart fresh strength to the electrilo cal impulses originallytransmitted, so that a much longer telephone-line can be successfullyoperated than has been heretofore possible. This device may also be usedas a receiver or transmitter, and several features of itsconstruction'are also claimed in this application.

One specific form of the general invention herein claimed is shown andclaimed in an application of mine filed July 25, 1883. In theaccompanying drawings, Figure Iis a diagrammatic View of my apparatusused as a relay, with the main magnet shown in section. Fig. II is aplan view of the main magnet, and Fig. III shows the apparatus as atransmitter or receiver.

In the drawings, Fig. 1,4 1s an electro-magnet having alongitudinally-perforated iron; core 3. The coils of the electro-magnetare.

in two sections t and at", the latter being in through the secondary oflnductlon-coil 6,

while the former is in a local circuit, to be hereinafter described.

\Vithin 'the hollow core 3 is a small needle or rod 7, of diamagneticmaterial, which at its central point is looped, up into a delicatespring 12, a vertical slot being left in the iron core to receive it.Spring 12 may be fast-' ened at the bend, if desired. Needle 7, with itsspring 12, may be inserted by having the magnet-core made in halves orin any other way. At one end of the needle 7 there is rigidly fastenedan armature-disk of soft iron 8, which is suspended by spring-arm 10,acting in opposition to spring 12. At' the other end needle 7 restsagainst and forms a microphonic contact with a carbon button 12, whichis faced with a perforated armatore-disk 9 of soft iron and suspended by50 spring-arm 11, also acting in opposition to spring 12. I

the mainrli'ne circuit 5, which also passes;

' The core 3 is rendered normally magnetic by the local circuit, whichgoes from battery 13 to coil 4', to spring 10, to armature 8, needle 7,carbon button 12', spring 11, primary of induction-coil 6, and back tobattery.

The operation of the device is accumulative or reactionary. Suppose atelephonic electrical impulse is transmitted over line 5, including coil4" and secondary of coil 6, of such a polarity as to coact with thecurrent of the local battery in coil 4: and strengthen the magnetism ofcore 3 instantly armatures 8 and 9 are attracted still more, themicrophonic pressure betweenneedle 7 and button 12 increased, a strongercurrent passes over the local circuit, increasing stillmore the strengthof coil 4.,and by induction-coil 6 sending a fresh impulse to main line5. This fresh impulse through coil 4" adds yet another increment to the.strengthfof core 3, which reacts on the 'microphonic contact and thestrength of the local circuit and continues the accumulative process. Ifthe primary impulse over the main line is of the opposite polarity, acorresponding reaction will be had.

The value of this instrument in long-distance telephony is apparent. Itis well known that an. electric current transmitted over a long linebecomes gradually dissipated by leakage and retardation, so that acurrent of .04 amperes at one terminal station will be re duced to .01amperes at the other terminal, or even, as in the case of telephoniccurrents with great electro-motive force and defective insulation,become practically lost.

By placing one of my relay-instruments at an intermediate point wherethe original current has not become too weak a fresh impulse is given toit, and it can be transmitted to the terminal station or another relay.

When used as a transmitter or receiver, a diaphragm 15, Fig. III, with asuitable mouth or ear piece, is placed so as to rest against armature 8,either directly or through the intervention of a metallic knob 16, whichis a continuation of rod 7. Asa transmitter it acts magnetically andelectrioally-magnetically by the effect of the vibrations of the irondiaphragm on the magnetic-condition of 100 core 3, which sets up inducedcurrents in coil 4: and the main line, and electrically by the as beforedescribed, as the result of which the varying attraction of the core forthe diaphragm is intensified and the original current itselfcorrespondingly strengthened. Although described as a series of steps,this accumulative action is practically instantaneous, and the effect isthe same as if the intensified action was an original one.

It will readily be seen from the fact that any change in the magnetismof core 3 instantaneously reacts upon itself to intensify such changethat any initial movement of diaphragm is automatically increased by theincreasing power of the core 3 acting at both ends on armaturcs 8 and 9and that carbon button 12' is held more firmly to the magnet. Therefore,however great the amplitude of the vibrations of the diaphragm, due toloud speaking or other cause, the carbon button will never be thrown outof contact with needle 7 and no rattling or obscure sounds betransmitted.

Having thus described my invention, the

following is what I claimas new therein and desire to secure by LettersPatent:

1. The combination of a continuous main line, transmitting and receivinginstruments therein, and a reinforcing device consisting of a localcircuit, means controlled by the main and local lines together forvarying the current in the local circuit, and an inductioncoil havingits primary in the local and its secondary in the main circuit.

2. The combination of an iron core, magneti'zing-coil surrounding thesame, an arma-' ture at each end of the core, and amicrophonic contactoperated by the joint action of the two armatures.

3. The combination of an electro-magnet and an induction-coil, theelectro-magnet having two coils, one in the main and the other in thelocal circuit, and the induction-coil having its primary in the localand its secondary in the main circuit, with means operated by theelectro-magnet for varying the current in the local circuit.

4. The combination of an electro-magnet having two coils and aninduction-coil, one of the magnet-coils and secondary of saidinduction-coil being in the line-circuit, a localbattery-circuit,including the primary of said induction-coil and theother magnet-coil, two armatures for the electro-magnet, and amicrophonic contact in the local circuit controlled by the joint actionof the armatures and the two circuits, as explained.

5. The combination of an electro-magnet, two armatures therefor, eachpressed by opposing springs, and a microphonio contact controlled bysaid armatures.

6. Thecombination of an electro-m'agnet, an armature at each endthereoflaperforated core,and a diamagnetic needle passingthrough saidcore and rigidly connected to one armature while makinga microphoniccontact with the other armature.

7. The combination of perforated core 3, needle 7, and spring 12 witharmatures, contacts, and circuits, as described.

8. The method, substantially as herein set forth, of reinforcingtelephone-currents,which consists in varying the current in one or morelocal circuits arranged alongithe line by the initial line-currents andaccumulating the variation by the increased local circuit, and causingsaid local currents to induce conspiring reinforcing-currents in theline.

9. The method, substantially as herein set forth, of reinforcingtelephone-currents,which consists in varying the current in one or morelocal circuits by the initial line-circuit and causing said localcurrents to induce conspiring reinforcing-currents in the'line.

w. A. WEST.

Witnesses:

E. M. BENTLEY, H. E. KNIGHT.

